In America the kids would be arrested for throwing the snowballs at an emergency worker, the fireman would have been fired then sued by the kids parents for spraying the kids and endangering their health and lives. I mean, after all, it could have given them their death of flu or blown them off the bridge.

As the Weeners in TFA rightly points out, that's not a firefighter. He's a worker using water pressure to clean the underside of the bridge. It looks like he also hosed the garbage on top of the bridge.